The connection quality of the narrow blind cavity of the aeroengine rotor has a great impact on the overall assembly quality of the rotor. The precise control ability of the bolt connection process is inadequate given the current domestic and international circumstances, which impact the connection mechanical properties of the mating surface of the rotor disc and shaft parts. This is because there is a lack of accurate and efficient assembly tooling for the blind cavity structure. Based on the above research status, according to the tightening assembly requirements of a certain type of blind cavity nut, the blind cavity tightening system is divided into a tightening torque transmission mechanism and an operation actuator. In the design of the tightening torque transmission mechanism, firstly, the torque method and torque angle method are compared to determine the torque angle method as the final execution process. The input and output torque model is established taking into account the torque loss to determine the input torque of the tightening tool in order to achieve high-precision control of the tightening torque. At the same time, the torque transmission structure is designed and the strength and longevity of important components are examined. In the design of the operating actuator, firstly, the mechanical design of the actuator and the 3DCS simulation of the high-precision moving parts worm gear and worm are carried out. At the same time, the trajectory planning and kinematics simulation are carried out by using MATLAB. Based on the aforementioned research, the blind cavity nut tightening technology is experimentally verified, and a perception system and control system for visual identification are built to achieve high-precision equipment control. It is of great significance to improve the quality and consistency of the blind cavity bolt array connection between the narrow disks.

Thin-walled metal parts with functional micro-featured surface have broad application prospects in the fields of resistance reduction, noise reduction, etc. In this study, a novel micro-rolling & incremental sheet forming hybrid process (μR-ISF) is proposed to fabricate thin-walled metal parts with microgroove arrays. An analytical model which relates the rolling force and microgroove depth in the micro-rolling stage was first established. Then, the formation mechanism of microgroove morphology during both micro-rolling stage and macro-shape forming stage are investigated. After the micro-grooved sheet being incrementally formed, a significant reduction (between 21% to nearly 60%) is occurred in the depth of both transverse and longitudinal grooves compared to the flat sheet. Meanwhile, the width of transverse grooves decreases slightly by about 10% on average, while the width of longitudinal microgrooves increases significantly by more than 30% on average. After micro-rolling, 85°{1012} tensile twins appear on the micro-grooved sheet and the percentage of 65°{1122} compressive twins increases. After incremental forming, the percentage of low-angle grain boundaries and the density of geometrically necessary dislocations in the formed part increase significantly, and the grain size distribution becomes more uniform. The present work provides a new strategy for the fabrication of 3D metal thin-walled components with surface micro-features.